JPS61502901A - New composite ceramic with improved toughness - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Background of the invention of a novel composite ceramic with improved toughness The present invention provides a novel refractory composite ceramic with improved toughness and the composite ceramic. The present invention relates to a method for manufacturing

Compared to non-composite ceramics, composite ceramics generally have superior toughness, strength, and resistance. Abrasive and suitable for machining high-strength alloys, rock drilling, and cutting other hard materials or cutting for forming [@ as a blade, high-temperature equipment or structural material, and For example, as wear-resistant, abrasion-resistant and chemical-resistant parts in certain chemical reactors. , exhibits excellent performance. Moreover, such materials can be used as wear-resistant surfaces. It can be used in spray nozzles and as impact-resistant materials. Ru.

A known method for producing refractory objects is to place them in tightly fitting, rigid molds. Heat pressing of powdered or compacted samples, or powdered or compacted samples An eye using a gas as a pressure transmission medium in a closed, deformable container containing Includes isostatic heat presses. What of these methods In both cases, the sample, whether initially as a powder or a compact, is or take the form of a modified container. Many problems arise when using this method. encounter. Limited dimensions and shapes of products that can be manufactured. complex form The final product with It has a strong density gradient. Also, each sample must be compressed in a separate mold or container. After hot pressing, samples are often placed in molds or containers during removal. adhere to.

Isostatic pressing of self-supporting compacts has the potential to overcome the above problems. proposed as a possible method. For example, Ballard and Hendricks rice National Patent No. 3,279,917 discloses a pressure transmission medium in heat pressing of refractory objects. teaches the use of particulate materials such as powdered glass or graphite. This person In this method, the particulate pressure transmission medium does not conform completely to the sample, and as a result As a result, pressure is also not transmitted uniformly and truly isostatically. parable For example, various shapes such as cubes, cylinders, etc. undergo distortion when pressurized. This person It is almost impossible to form a rough contour by the method.

Pervalus U.S. Patent No. 455,682 discloses a fire-resistance system comprising the following steps: Discloses a method for improving isostatic heat pressing of objects = (A) essentially from about 5% to about 40% by amount of alkali and alkaline earth metal chlorides, fluorides and 60-95% by weight of a first component selected from silicic oxides and mixtures thereof; silica, alumina, zirconia, magnesia, calcium oxide, spinel, a second component selected from lite, anhydrous aluminosilicates and mixtures thereof; (B) surrounding the object with a mixture that makes it plastic; and (C) while maintaining the temperature, the mixture is heated at a temperature of Apply enough pressure to increase the temperature. In this way, various shapes and sizes refractory objects of low porosity having a process that substantially alters their initial form. It can be compressed to extremely high densities with extremely low porosity without It is written that

Rozmus U.S. Pat. To strengthen metallic and non-metallic composition materials and combinations thereof Discloses a method for seri, in which a material having a density lower than a predetermined density is used. A certain amount of such material - envelops the bone in a pressure transmitting medium and By applying external pressure to the and by being able to flow, at least until just before the predetermined densification. a given density of the encapsulated material due to the hydrostatic pressure exerted by the medium. cause densification. This invention provides fluid flow in response to collapse of the skeletal structure at a predetermined force. For the formation of a composite of skeletal structure fragments dispersed in the mobilization means and for the given density of the shaped body. In order to make the composite completely dense, incompressible and fluid during densification, Pressure transmission in rigid, interconnected skeletal structures that can collapse in response to a given force. A flowing medium supported by and retained within the delivery medium and skeletal structure. It is characterized by the use of a fluidizing means that can.

Achieving hydrostatic densification with a completely dense and incompressible medium during pressing The press must provide sufficient force to cause plastic flow of the media. It is written that it must be done. The medium becomes very fluid or sticky It is desirable to heat the medium to a temperature sufficient to prevent it from occurring. However, the medium so that it can be handled for placement in the press without changing its external shape. , must maintain its external shape during and after heating. Skeletal structure is the lowest force Compared to plastic flow, it is crushed or squeezed and dispersed into a fluidized material, which provides a small amount of resistance, thereby compacting the powder hydrostatically. Hidden When the skeletal structure collapses, the pressure applied by the press becomes hydrostatic. is transferred to the powder.

Composite ceramics, such as those typically made from tungsten carbide and cobalt, It is made of refractory materials such as tungsten carbide and cobalt. It is produced by bringing metals into contact under conditions where the metals become liquid. It will be done. Under such conditions, the refractory material partially dissolves into the metal and subsequently precipitates from the metal as it cools. This manufacturing method includes a liquid-solid process. During this process the metal acts as a wetting agent and the refractory material is prominent during precipitation. causes agglomeration.

This agglomeration results in the formation of extremely brittle composite ceramics.

Generally, composite ceramics manufactured by the above method are extremely hard. Unfortunately, it is extremely brittle (i.e., has no toughness). Such brittleness causes cracks to provide a composition that is susceptible to initiation and growth and has very low impact strength. . Demand for composite ceramics with desirable toughness without sacrificing hardness has been done.

Summary of the invention The present invention relates to oxides, carbides, nitrides, silicides, borides, sulfides and mixtures thereof. refractory material selected from the group consisting of compounds and reducing the gaps between the refractory material particles. a plastically deformable binder material present in sufficient quantity to partially occlude the spider; approximately 10% greater toughness than that exhibited by other composite materials of similar composition. , a high-density refractory composite ceramic consisting of densified refractories.

Another aspect of the invention is: (al　oxides, carbides, nitrides, silicides, borides, sulfides and mixtures thereof at least one phase of a refractory material selected from the group consisting of; (bl) at least one phase of binder material capable of plastic deformation; and (c) At least one phase in which atoms of the mixture material are substituted on the lattice of the refractory material: consisting of a binder material and a component e(c) which reduces the gaps between the refractory material particles. It is a high-density composite ceramic present in sufficient quantity to at least partially block the reservoir. Ru.

Another aspect of the invention is a group consisting of oxides, nitrides, borides, silicides and sulfides. refractory material selected from the loop and at least part of the interparticle gaps of the refractory material particles. A plastically deformable binder material present in sufficient quantity to partially block the At a temperature below the liquidus temperature of the composite material; approximately 10.0OOpsi (bond/flat) (6,89 x 10” MPa) and the breaking point of the refractory , sufficient time and baking time for the composite ceramic to reach a density of 85% of its theoretical density. 85 of the theoretical density for a period of time less than sufficient for the formation of % or higher than that exhibited by other composite ceramics of similar composition and density. contact under conditions that give a dense refractory body with 10% greater toughness. A method for manufacturing the high-density refractory composite ceramic comprising:

The high-density composite ceramic of the present invention has similar composition and Exhibits greater toughness than other composite ceramics with geometries. Moreover, the present invention This method is achieved in less harsh conditions and in less time than previously known methods. It will be done.

The invention generally relates to an improved refractory ceramic material combined with a binder material. The present invention relates to a high-density refractory composite ceramic having superior toughness. of the present invention One component of the ceramic composition is a refractory ceramic material. generally fire resistant Any ceramic material is useful in the present invention. Suitable refractory ceramic material Materials include refractory oxides, refractory carbides, refractory nitrides, refractory silicides, and refractory borides. refractory sulfides and mixtures thereof. More suitable fire-resistant ceramic material Materials include refractory alumina, zirconia, magnesia, mullite, zircon, doria, beryllia, urania, spinel, tungsten carbide, tantalum carbide, titanium carbide , niobium carbide, zirconium carbide, boron carbide, hafnium carbide, silicon carbide, carbon Niobium boron oxide, aluminum nitride, titanium nitride, zirconia nitride, tanta nitride hafnium nitride, niobium nitride, boron nitride, silicon nitride, titanium boride, boron Chromium chloride, zirconium boride, tantalum boride, molybdenum boride, tantalum boride ungsten, cerium sulfide, molybdenum sulfide, cadmium sulfide, zinc sulfide, sulfide Includes titanium, magnesium sulfide, zirconium sulfide or mixtures thereof.

Even more suitable refractory ceramic materials include tungsten carbide, niobium carbide, and china carbide. Tan, boron carbide, alumina, silicon nitride, boron nitride, titanium nitride, titanium boride or mixtures thereof. An even more suitable ceramic material is tan carbide. Gusten, niobium carbide and titanium carbide. The most suitable fire-resistant ceramic material The material is tungsten carbide.

Generally, the binder material useful in the present invention is any metal that is capable of plastic deformation. It can be defined as a genus, a metalloid, an alloy, or an element that forms an alloy. suitable bond Agent materials include cobalt, nickel, iron, tungsten, molybdenum, and tanta%y' 7-o gas=obium, boron, zirconium, vanadium, silicon, palladium, haf aluminum, copper, alloys thereof or mixtures thereof. even more Suitable binder materials include cobalt, nickel, titanium, chromium, niobium, boron, and Radium, hafnium, silicon, tantalum, molybdenum, zirconium, vanadium aluminum, copper, alloys thereof, or mixtures thereof. even more suitable Typical binder materials include cobalt, chromium, nickel, titanium, niobium, palladium, and Fungium, tantalum, aluminum, steel, or mixtures thereof. Sara More suitable binder materials include cobalt, niobium, titanium or mixtures thereof. do. The most preferred binder material is cobalt.

Generally, a binder material at least partially fills the interstices between the particles of the refractory ceramic material. be present in sufficient quantity to obstruct. The binder material is particles of refractory ceramic material Preferably, it is present in sufficient amount to fill the gaps between. composite ceramics The refractory body contains about 0.5% to about 50% binder material by volume and about 50% to about 9% by volume binder material. Preferably, it is comprised of 9.5% refractory ceramic material. The composite cell of the present invention Lamic refractories contain about 0.5% to about 30% binder material by volume and about 70% by volume % to about 99.5% refractory ceramic material. compound cell Lamic refractories have a binder material of about 6% to about 20% by volume and about 80% by volume. Even more preferably, it is comprised of about 94% refractory ceramic material.

In preferred refractory body composite ceramics, the refractory ceramic material is at least about Contains 85% single refractory ceramic compound. Most suitable specific example odor The refractory ceramic material is at least about 90% of a single refractory ceramic material. It includes.

The present invention further relates to a novel composite ceramic composition comprising at least the following three phases: It is: (al　Glue consisting of oxides, carbides, silicides, borides, nitrides and sulfides) (b) at least one phase of a refractory material selected from at least one phase of a binder material such as: and (cl At least one phase consisting of a compound corresponding to the formula Xa-bYbzo, the formula Inside Is X a group consisting of oxides, carbides, nitrides, silicides, borides and sulfides? It is a metal derived from a refractory material selected from: a binder material capable of plastic deformation. carbon, oxygen, nitrogen, silicon, boron, or sulfur; a is about 1 to Extract with an integer of about 4: b is a real number from about 0.001 to about 0.2; and C is an integer from about 1 to 4. .

A review of the three-phase cobalt-tungsten carbide composite ceramic composition described above. Composite ceramics of three or more phases consisting of other materials as defined herein. It is acknowledged that mixes also exist.

(Al phase is considered to be a phase in which the binder material atoms are substituted on the lattice of the refractory material.) It will be done. Furthermore, in the ceramic composite of the present invention, these compounds are The bond between the binder material phase and the refractory ceramic material particles in the interstices between the ceramic material particles. It is thought that this is possible. The presence of such a phase indicates that the ceramic composite of the present invention This is thought to be responsible for the markedly improved toughness of . In the above formula, b is approximately o, ooi to about 0.1 is preferred. This three-phase ceramic composite is about 50 to about 99% refractory ceramic material by volume; about 1 to about 50% bond by volume and about 0 to about 0.2% by volume of Formula Xa-bYbz. (Here x, y , z, a, b and C are as above) is preferable. The composite ceramic of the present invention has a capacity of about 70% to about 98% refractory ceramic. about 2% to about 30% by volume binder material; and about 0% to about 0.0% by volume binder material; More preferably it consists of 2% of a compound corresponding to formula Xa-bYbzo. composite Ceramic is about 80% to about 94% refractory ceramic material by volume; about 2% to about 94% by volume about 3ON of the binder material; and about 0.001 to about 0.1% by volume of the formula Xa-bY It is also preferable to consist of a compound corresponding to bzoK. X is aluminum, Zirconium, magnesium, thorium, beryllium, uranium, tungsten, Tantalum, titanium, niobium, boron, hafnium, silicon, chromium, molybdenum, Preferably it is cerium, cadmium or zinc. X is tungsten, niobium More preferably, it is aluminum, titanium, silicon, tantalum, boron or aluminum. stomach. Even more preferably, X is tungsten, niobium or titanium.

It is also preferred that X is tungsten. Y is cobalt, nickel, iron , tungsten, molybdenum, tantalum, titanium, chromium, niobium, zirconium Preferred are aluminum, boron, vanadium, silicon or radium. Y is Ko Balt, nickel, titanium, chromium, niobium, palladium, boron, silicon, tan More preferably, it is metal, molybdenum, zirconium or vanadium. Y is cobalt, chromium, niobium, nickel, titanium, palladium or tantalum. Even more preferably. Y can be cobalt, niobium or tantalum Even more preferred is cobalt. 2 is carbon, nitrogen, Preferably it is boron or oxygen. 2 may be nitrogen, carbon or oxygen. Carbon is particularly preferred.

In the present invention, toughness is defined as the energy absorbed when a standard sample breaks. do. Toughness when used in the present invention is defined as "material strength" by Marlin, 1 be quantified by a toughness index that is substantially the same as that used on page 6. However, the toughness index depends on the nearly linear stress-strain behavior (i.e., elastic response) is equal to the area under the stress-strain curve and can be determined by the following formula: can be done: The elastic modulus of the stress-strain (straight line) relationship passing through the origin (i.e. f+) is , is equal to the value obtained by dividing the vertical axis by the horizontal axis, so the toughness index is (fracture) in the elastic region. stress up to break) 2 2.Modulus of elasticity be equivalent to. As an alternative to the stress versus fracture relationship, a standardized and convenient transverse fracture You can use the breaking strength value.

In addition to exhibiting great toughness, the composite ceramics of the present invention generally have similar compositions. exhibits at least equal hardness compared to other composite ceramics with and shapes . Most materials of interest in the present invention have high hardness (and usually correspondingly limited The product of hardness and toughness index is an advantage. It can be used as an indicator.

The composite ceramic of the present invention is generally compatible with other composite ceramics having similar composition and shape. It represents the hardness-toughness fact to a greater extent than the hardness. i.e. without sacrificing hardness. , exhibiting greater toughness.

The composite ceramic of the present invention preferably has a diameter of about 10 microns or less, more preferably about 5 microns or less. Micron or less: even more preferably about 2 microns or less, even more preferably about 2 microns or less It has an average grain size of 1 micron or less.

The particle geometry partially contributes to the improved properties of the composite ceramic of the present invention. It seems that there are. Relatively small round or oblong particles have improved properties. It seems that it is caused by

Composite ceramic high-density refractory consisting of a refractory ceramic material combined with a binder material The object is manufactured in a substantially solid state process. What is solid phase process? The book describes methods for bonding binder materials and refractory ceramic materials while in the solid state. Refers to order. The formation of a third phase or other additional phase in the composite ceramic of the present invention This appears to be evidence of solid phase processes occurring during the manufacture of such composite ceramics. It will be done. In general, binder materials and refractory ceramic materials, in their powder state, are The ceramic material and the binder material can be used in a container that can act as a delivery medium. To form a composite ceramic bonded by a binder material capable of plastic deformation at a sufficiently high temperature. This is usually the case with powders that come into contact. Fill the container and use vacuum suction to remove all gas contained in the container, then seal it. . Alternatively, the binder material and the refractory ceramic material can be formed into a compact by cold-pressing kumite. Preforming may also be used, but in this case 1 the material thus formed is not yet fully densified. It's not crowded. Generally, the metal and ceramic powders are preferably about 10 microns less than 2 microns, more preferably less than about 5 microns, even more preferably about 2 microns The particles preferably have a particle size of about 1 micron or less. suitable grain Size descriptions are given for substantially unimodal particle size distributions. specialized in this field The house accounts for the main proportion of fine particles, with a small proportion of the particles considerably smaller in size. By mixing K with particles, relatively high packing densities can be achieved for a given degree of compaction. You will recognize that it is possible to achieve a degree.

A bonded composite ceramic is herein defined as one whose integrity is maintained by binder particles. A ceramic composite that is sagging.

The conditions for bonding the binder material and the refractory ceramic material provide significantly improved toughness. This is important in the production of composite ceramics having a refractory body. Desirable 3 One parameter is the temperature at which the bonding proceeds, and the temperature to achieve such bonding. the pressure used and the time such pressure is applied. Furthermore, the pressure is It is desirable to add it isostatically. Isostatic In this specification, hard pressure refers to the material to be densified, regardless of its shape or dimensions. means applying pressure uniformly to all parts of the not fully densified Equal dimensions in all axes as a result of isostatic pressure on the material A decrease in

The specific pressure, temperature and time in the tank that will yield the desired result will depend on the specific combination selected. Depends on the agent material and refractory ceramic material. Experts in this field will appreciate the information provided in this specification. Specific pressures, temperatures and times could be selected based on the following.

Temperatures useful in the present invention are below the liquidus temperature and below the solidus temperature. It is preferred that the cold-pressed portion has a theoretical density of about 99% when held for 8 hours without pressurization. % is also preferred. For the purpose of the present invention , the liquidus temperature is defined as the binder material force; the solid force λ and the liquid state (i.e. completely liquid ) is the temperature at which the phase change occurs. The solidus temperature is the temperature in a mixed phase system without the application of pressure. is the temperature at which plastic deformation occurs (i.e., it first begins to melt). solidus temperature The degree of plastic deformation is presumed to be exceeded if it occurs without the application of crab pressure. It will be done. If the liquidus temperature is unknown, it can be determined by standard methods known to those skilled in the art. It can be calculated using a suitable method. Applicant has determined that the bonding material is in a substantially liquid state. The densification of the binder material and the refractory ceramic material at a certain temperature generally A hardened object that has a toughness much lower than that formed at temperatures where it is in the solid state. We have found that it gives The temperature is approximately 100,000 psi (6,89 xl O'MPa) pressure to achieve 85% theoretical density within 1 hour. It is preferable that the temperature is higher than the degree. Temperatures useful in the present invention range broadly from 400 to 2 The temperature is 900°C. The temperature that is useful for a particular bonding material depends on the nature of that bonding material. It must be recognized that it depends on the quality, and experts in this field The useful temperature could be determined based on the functional description provided. Generally preferred Preferably, the temperature is about 60% to about 95% of the melting temperature (°C) of the bonding material. More preferably, the temperature is about 75% to about 85X of the melting temperature (° C.). part suitable binder materials and those binder materials that can be used in the present invention. The temperatures for cobalt are approximately 800-1500°C; More preferably from about 1000°C to about 350°C; for nickel, about 850°C ~1455°C; approximately 720-1865°C for chromium; chromium-nickel alloy about 700-1345°C for niobium; about 800-2475°C for niobium; About 1275-1415°C for silicon; 1800-210°C for boron 5°C; tantalum approximately 1050-2850°C; for tantalum-niobium alloys, approximately 900-2550°C; about 1 O15-13 for cobalt-molybdenum alloy 35°C; about 400-1650°C for niobium-tantalum-titanium alloys; and Approximately 700-1855℃0 for vanadium Preferably, the pressure is applied isostatically. Pressure is maintained permanently in the composite ceramic. Add at sufficient volume to cause permanent volume loss (i.e., densification). The pressure is approx. 10,0OOpsi (6,89X10’MPa) and fracture of refractory composite ceramic Preferably, it is between the breaking points. The pressure is approximately 50,000 psi (3,45 0”MPa) and the breaking point of the refractory composite ceramic: approximately 70. Be between OOOps i (4,82X 10'MPa) and the breaking point more preferably; and about 100,0OOpsi (6,89 x 10'' MPa). It is also preferred that it be between the breaking points.

The pressure is 1 at temperatures below the liquidus temperature of the phase mixture or binder material itself. To densify a cold compact of powder composite to a density of at least 85% in less than an hour. It must be sufficient for The pressure is adjusted to achieve the above densification in less than 1 minute. preferably sufficient, and sufficient to be accomplished in less than 10 seconds. It is more preferable that Approximately 1.000psi/sec (6,89X10'MP A pressure rise rate higher than 10,000 ps i/5ee) is preferred; A pressure increase rate of greater than sec is more preferred. If the pressure used is too high If the pressure used is too low, there is a risk of destruction of the refractory material being manufactured. In some cases, the refractory objects produced have a tenacity that is too low for the desired use.

The time of use shall be sufficient to densify the refractory to the desired density. . The time the refractory object is exposed to the desired pressure is such that the ceramic composite reaches its theoretical density. Enough time to reach 85% and enough time for the material to undergo sintering. It is for a few minutes. The time period between about 0.01 seconds and 1 hour is generally oppressive and dense. It is suitable for achieving A more favorable time for achieving the desired densification is Less than 1 hour, even more preferably less than 10 minutes, even more preferably less than 1 minute. A time of less than 10 seconds is preferred.

Practical considerations governing the selection of appropriate time, temperature and pressure variables in the present invention It must be recognized that the term exists. In general, the time variable is The temperature range is high enough to begin to cause noticeable shape changes and coarsening. should be kept to a minimum (within the usefulness of the present invention) in order to avoid this. deer while the temperature is high enough to minimize pressure requirements on the equipment. Must be high.

Both high pressure and high temperature promote flow. Therefore, the stones grow too large. Both must be made as high as possible, subject to the constraint that . For those skilled in the art, one of the greatest benefits and most surprising results of the present invention is The first is to provide excellent The reason is that it is possible to manufacture composite ceramics with toughness. Despite the fact that stone growth inhibitors may be used to extend the scope of practice of the present invention, It is obvious that it can be done.

Isostatic pressure is applied to powdered binder materials and ceramic refractory materials. , or can be added to pre-pressed powdered binder materials and refractory materials. . Methods for such isostatic pressurization are known to experts in this field. and allows the use of limited parameters of time, temperature and pressure as described above. All such methods are useful.

To transmit isostatic pressure to the materials to be bonded and densified One preferred method is described in Roseas U.S. Pat. (incorporated herein by reference).

The method described therein first involves combining binder material and ceramic in the desired proportions. The powder of the bulk material is heated to the temperature and pressure used for densification of the powder to form a pressure transmission medium. This includes placing it in a container that can behave as a body. That is, this The container is flexible or deformable at elevated temperatures but retains structural integrity. I must stand. Powdered binder material and powdered refractory ceramic material in a container. Before contacting, the container is vacuumed and the powder is placed into the container under vacuum conditions.

This container containing the relatively less dense powder is then placed into a casting mold and its The whole container and the less dense powder are removed by pouring the pressure transmitting medium into the container conduit. Wrap the material. By solidifying the pressure transmission medium, it retains its external shape and Remove from the mold. A pressure transmission medium is a hard material that collapses when a given force is applied. It contains a skeletal structure that is interconnected. The skeletal structure is hard and maintains its external shape. but can collapse, shatter or split under a relatively small given force. The material may be made of a ceramic-like material. The skeleton structure is made of ceramic It is defined as a material that is bonded together to form a framework, lattice, or matrix. be justified. The pressure transmission medium is further supported by and retained within the skeletal structure. The patent covers the fluidizing means, i.e., the fluidizable material.

The fluidizing material may in particular be a glass or an elastomeric material.

In other words, the structure of the skeleton is such that the glass particles are held and supported by the skeleton structure. Distributes electricity into gaps or spaces. A preferred transmission medium is a slurry of structural material The particles of the activating material are dispersed by mixing in a wetting fluid, i.e. an activating agent. It can be formed as follows. Densify encased materials that are not completely dense Before heating to compression temperature. This involves putting the wrapped container and the powder into the furnace. This is done by raising the temperature at which compression occurs at the desired pressure or force. I can do it. During such heating, the glass or its Other fluidizable materials soften and become fluid and allow plastic flow, resulting in dense At the compaction temperature at which the powder is heated for oxidation, its morphology is lost without the skeleton structure. become unable to maintain it. The heated pressure transmission medium can be placed inside the pot mold. After being heated to the compression temperature, it can be removed without losing its shape. can be handled. Pressure transmission medium enclosing the container and the relatively loose powder The body is then; a cup-shaped body with an outer wall extending upwardly from the upper end of the pressure transmission medium; Place in a press, such as one with a pot mold. After that, press the ram Move downward into tight sliding engagement with the inner wall to engage the pressure medium.

The ram thus applies a force to a portion of the outer pressure transmission medium while the pot mold Constrains the remainder of the pressure transmission medium, thereby applying the desired external pressure to the entire pressure transmission medium. When applied to the external surface, the pressure transmitting medium is a fluid that densifies the powder to the desired consistency. Acts as a fluid to apply static pressure. Pressure transmission medium for external pressure When added to the fluid, the skeletal structure becomes fractured and dispersed within the fluidization means. , the pressure applied by smelting contains the powder to be directly densified by the fluidizing means. transmitted to the container.

Thereafter, the densified material encapsulated within the pressure transmission medium may be cooled. Hidden In this case, the pressure transmission medium becomes a hard and fragile ridge-like structure, which can be used for example in a hammer It can be removed from the container by crushing it by hitting it with a can.

Densification of powdered binder materials and refractory ceramic materials using isostatic pressure One suitable container useful for (the relevant parts of which are hereby incorporated by reference) . This patent describes a heat compressed powder consisting of substantially completely dense and incompressible material. containers and containers within which materials can plastically flow at pressurized temperatures; When the walls of the container are sufficiently thick, the container material will exert hydrostatic pressure against the powder. Discloses that it acts as a fluid in the application of heat and pressure to give 0 Under these conditions, the outer surface of the container has the outer shape of the desired refractory object to be manufactured. does not need to match.

Such containers maintain their structural integrity at pressurized temperatures but are subject to plastic flow. It can be made of any material that can. Among the acceptable materials are low carbon steels. , other metals, glasses or ceramics with the desired properties. Special The selection of certain materials depends on the particular binder material and the temperature at which the refractory ceramic material is densified. Depends on. - In comparison, two pieces of material used to make the container were machined to A mold having a mold part and a lower mold part is manufactured. Next, the upper mold part and the lower mold part of them so that they form a cavity with a predetermined desired contour. Join them together along their mating surfaces. The dimensions and shape of the cavity should be manufactured Determine depending on the final form of the part. 6 Before combining the upper and lower mold parts, Drill a hole in one mold part and insert the charging tube. After installing the charging tube, both types Welding the parts together in mating relationship. Allows vacuum suction during welding Care must be taken to ensure that a suitable seal is provided. That one Immediately, the container is aspirated and the powder to be densified is charged through the charging tube. Then the outfit The entry tube is clamped closed and sealed by welding.

The container is then isostatically placed at the desired bonding and densification temperature. expose to pressure. This can be done by the method described above. Alternatively, Place the loaded and sealed container in an autoclave, such as an argon gas autoclave. Exposure to desired temperatures and pressures for bonding and densification in an autoclave. You can also do it. The pressure on the container in the autoclave is isostatic and The container can maintain its shape and has plastic-like tendencies Therefore, the container exerts an isostatic pressure on the powder to be densified.

The dimensions of the cavity in the container are such that the powder within it shrinks to the desired density. Ru.

After compression, the container is removed from the autoclave and allowed to cool. Then nitric acid solution The container is removed from the densified refractory material by pickling inside. With another method by machining or by a combination of rough machining and subsequent pickling. The container can then be removed.

In another method, it may adversely affect the desired properties of the densified product. Thick-walled containers are made from materials that melt under unusual temperature and time combinations. can be made. These recyclable packaging materials are used by Risunbee rice. National Patent No. 4,341,557 (the relevant portions are incorporated herein by reference) (disclosed in) In practicing the present invention, the above-mentioned U.S. patent reproduction Prepare a container as described in line 31,355 and pre-register for such container. Isostatic pressure can be applied as shown below. Powdered binder After densifying the material and the refractory ceramic material, the refractory thus produced Expose the container to a temperature at which it melts without affecting the properties of the object.

The molten material or metal that has melted away from the refractory is then transferred to the form of a new container. can be reused for construction.

Barbaras U.S. Pat. ON alkali and alkaline earth metal chlorides, fluorides and silicates; and about 60% to about 95% silica by weight; Alumina, zirconia, magnesia, calcium oxide, spinel, mullite, free Another pressure consisting of a second component selected from water aluminosilicates and mixtures thereof A transmission medium is disclosed. This pressure transmission medium can be used as follows: can. First, the mold in which densification is to be performed, that is, the combination cavity, is The material to be densified by cold compression of a portion of the pressure transmission medium at the bottom of the mold A The pre-compacted billet provides a base on which to place the pre-compacted semi-finished product and then pre-compacts the billet. by placing it on its base and further covering it with a pressure transmission medium. is preferable. The mold is then heated to a temperature at which densification is to take place and its contents are is equilibrated at this temperature. After that, the desired pressure to stop densification has already been applied. Add to the plasticized pressure transmission medium. After the pressure is removed, heat pressurization equipment is applied. inside the billet by quickly removing the mold from the heating area and cooling it rapidly. It is preferable to minimize the growth of stone grains. compacted body, i.e. densified The fused pressure transmission medium containing the flammable material is removed from the mold and the outside of the fused pressure transmission medium is removed. Break the cover and recover the compressed refractory material. The process method is hard heat press Although it is convenient to use a mold, this method sealed, deformable containing one or more billets surrounded by one of the compounds It can also be done by exposing the container to high temperature and isostatic pressure. can.

Other applications for subjecting refractory ceramic materials and binder materials to isostatic pressure The method is described in U.S. Pat. (incorporated herein); Rosmus U.S. Pat. No. 4,142,888 ( (Relevant portions are incorporated herein by reference); Rozmus U.S. Patent No. 4, No. 255,103 (relevant portions are incorporated herein for reference); Bobro U.S. Pat. No. 3,230,286 to Ski (relevant portions are hereby incorporated by reference) No. 3,824,097 to Smythe et al. (incorporated herein by reference); Rorsch U.S. Pat. No. 4,023; No. 466 (relevant portions are incorporated here for reference); Kirktreet No. 3,650,646 (incorporated herein by reference with relevant portions) No. 3,841,870 (with relevant portions); (incorporated herein by reference); US Pat. No. 4,041,123 to Rank et al. (The relevant portions are incorporated herein by reference); Larson U.S. Patent No. 4, 077, No. 109 (all related parts are incorporated herein as reference); Adler No. 4,081,272 to Bourne, incorporated herein by reference with relevant portions. and Isaacson et al., U.S. Pat. No. 4,339,271 (related (The portions that follow are incorporated herein for reference).

In practice, the pre-compacted bonding material and refractory ceramic material are bonded and refractory. A powder of fire-ceramic material may be placed in a press to partially densify this material. It can be prepared by: The resulting partially densified material is a billet. It can be called ``to''. Such compression is normally performed at room temperature. -Ingredients In one example, a hard graphite mold can be used to apply pressure. suitable The pressure generally ranges from about 200 psi (1,38 MPa) to about 10,000 psi ( 6,89×10'MPa). Alternatively, binder materials and refractory ceramic materials The raw material powder can also be pressed directly into a steel or tungsten mold in a powder metallurgy press. can. Then, the powder is placed in a thin-walled rubber mold 5, and the mold is inhaled and sealed. Afterwards, at room temperature and about 1,000+) si (6,89X10'MPa) to about 10 Eyes in a liquid medium at a pressure of 0,000 psi Can be exposed to sostatic pressure. - In a preferred embodiment, partially concentrated The densified binder material and the refractory ceramic material are about 30X or greater, more preferably about having a density of 50 to about 85%, most preferably about 55 to about 65%. .

The dense refractory ceramic composite of the present invention is about 85% or more, preferably about 90X or more, more preferably about 95X or more, and most preferably about 100% density. have. High density, as used herein, means a density of approximately 90X or more of theory. do. These products are smaller than refractory objects produced by conventionally known methods. It has a small particle size. Moreover, the refractory objects of the present invention can be manufactured by conventional methods. It has an increased dispersion than that of a refractory body. A surprising feature of the invention is that This means that high toughness is achieved even when full density is not present.

This feature becomes more pronounced as the density decreases to about 85%. Composition of the invention Even at slightly lower densities, the same exhibits a toughness equal to or greater than that of the composition. Relatively little amount of fire-resistant material There are products that have greater toughness at higher agglomerations and desired hardnesses. It seems to be.

1 than other composite ceramics with similar composition and shape. It is preferable that A has 0% greater toughness. The composite ceramic according to the present invention is It is more preferred to have a toughness of 15% greater, and a toughness of 25% greater. It's always good to be there. This increase in toughness is similar to that of others with similar composition and shape. achieved while maintaining at least equal hardness compared to composite ceramics of Ru. In addition, the composite ceramic of the present invention is generally comparable to other composite ceramics of comparable hardness. It has higher lateral fracture strength than lamic. The composite ceramic of the present invention Known applications for the Includes applications requiring materials with toughness.

For those skilled in the art, the products formed in the solid phase and the phase diagram are known and available. (e.g. scanning electron microscope, optical microscope or analytical transmission electron microscope) A liquid phase can be formed between the alloy composition (which can be observed by microscopy) The existence of additional ceragra-phic distinctions It should be obvious.

The microstructure of the composite ceramic of the present invention is such that the composite ceramic has relatively small grains. size, better dispersed binder materials (e.g. tungsten carbide-cobalt cobalt in composite ceramics) and having an almost circular grain shape or outline. and necessary to resolve the characteristic grain size and morphology of composite ceramics. Depending on the required resolution, optical microscopy, scanning electron microscopy, replica microscopy Transmission electron microscopy measurement is used for measurement and analysis. The magnification of the stone grain is known and Regardless of the microscopic measurement method used, as long as sufficient resolution is obtained, virtually no The acquired data can be processed in a similar manner.

The ceramics of the present invention generally have mostly circular or oval grains (or mostly It has a characteristic stone grain cluster formed by circular protrusions.

Other composite ceramics generally have more angular morphologies (i.e., more polygonal morphologies). ) and the binder phase tends to collect as angular pockets; Therefore, 2.3 of these square grains are connected or collided with each other.

Microscopic measurement methods generally rely on examination of flat sections of the sample. The composite cell of the present invention Lamic appears to be roughly circular or oval, whereas other composite Ceramics are generally shaped like irregularly shaped polygons with 3 to 8 or more sides. It appears as

The composite ceramic of the present invention preferably has a diameter of about 10 microns or less. Preferably about 5 microns or less, even more preferably about 2 microns or less. Below that, all four preferably have an average grain size of about 1 micron or less.

In addition, the composite ceramic of the present invention has a better dispersed binder material. Ru. When drawing a straight line on a microstructure diagram, the line is a and more often cross grain boundaries (of refractory materials).

Moreover, when there is a better dispersion of binder particles in the diagram, the straight line is better In a material with dispersed binder particles, the binder particles are frequently traversed. series The average number of binder particles (i.e., binder distribution) crossed by parallel straight lines of Compared to other composite ceramics made of is large. The percentage increase in binder distribution for the composite ceramic of the present invention is similar to It is preferably about 10X larger than other composite ceramics of the composition. Binder distribution is more preferably about 50% greater than other composite ceramics of similar composition; It is also preferred that the layer be about 100% larger. The composite ceramic of the present invention is relatively High loading power, relatively high pressure rise rate (i.e. short loading time) and relatively low temperature Because of the processing conditions, which include a greater degree of binder distribution. line on image Convert the length of the observed line to its absolute value by dividing the length by the magnification factor. If so, images of different magnifications can be used.

Another notable feature of the composite ceramics of the present invention is their low circularity (circ ularity) value. Circularity is calculated by dividing the square of the circumference of a stone grain by its area. It can be defined as a value. Grain grains are more circular (i.e. more circular) , the smaller the calculated circularity value.

The dimensions of the circle give a minimum circularity value equal to 4π or about IZ6.

A regular octagon has a circularity value of about 13.25, while an irregular polygon has a circularity value of about 20. Adjust the circularity value that exceeds. The average circularity is the typical degree of stone grain in the g-microscopic measurement diagram. It is calculated by taking the average circularity of the samples.

Composite ceramics of the present invention preferably have less than about 17, more preferably about 15.5 even more preferably less than about 14, most preferably less than about 13.5 It has an average circularity value b.

As a comparison, the average circularity value for other composite ceramics of similar composition is around 20. It's also huge.

The method of the present invention enables the production of refractory objects of composite ceramic materials with controllable toughness and hardness. construction.

In one preferred embodiment, the binder material is cobalt and the refractory ceramic material is cobalt. It is tungsten carbide. The above composite ceramics have a capacity of about 0.5 to about 50%. of cobalt and about 50 to about 99.5% tungsten carbide by volume. preferable. The composite ceramic contains about 0.5% to about 20% cobalt by volume and about 20% cobalt by volume. More preferably, the compound is comprised of about 80 to about 99.5X tungsten carbide. The composite ceramic is approximately 6% cobalt and 94% tungsten carbide. Most preferably, it consists of: The above tungsten carbide-cobalt composite ceramic tungsten carbide-cobalt ceramics with similar composition and shape. It has greater toughness than wood. Tungsten carbide-cobalt ceramic of the present invention It is even better that the mix has IOX greater toughness, 15% greater toughness It is even more preferable to have a toughness that is about 25% greater. It is even more preferable to have about 50% greater toughness.

The toughness of tungsten carbide-cobalt composite ceramics is greater than approximately λIMPa. b, preferably about 3 MPa or more, more preferably about 4 MPa or more It is also preferable that The hardness of these composite ceramics is approximately 1100 VHN or higher is preferred, and approximately 1600 VHN or higher is even more preferred. Precisely: For different hardness scales, the ceramic composition has a hardness of about 80R. It is preferable to have a hardness of about 95Rc or more, and even more preferably about 95Rc or more. preferable. Refractory objects made from cobalt and tungsten carbide are approximately 10 microns thick. or less, more preferably about 5 microns or less, still more preferably about 2 microns or less It may have a particle size of less than 1 micron, most preferably less than 1 micron.

The following examples are included for illustrative purposes only and are intended to illustrate the present invention or claims. It is not intended to limit the scope of. Unless otherwise specified, number of copies and hundred The fraction depends on the volume.

Example 1 Weigh fine tungsten carbide (23.5 g, particle size less than 0.5 microns) and powder it. Mix with powdered cobalt (1.5 g). This composition is 94% by weight (by volume) 90X) of tungsten carbide and 6% (10% by volume) of cobalt. both The powder is vibrated milled for 8 hours to coat the tungsten carbide with cobalt. Approximately 0. 5% by volume (o, xz 5g) of wax is added to aid in the formation of the cold compact. cold forming The body can be preformed using a uniaxial press or a silastic liquid mold with a density of approximately 559. It is caused to form by causing a film to form. The mold pressure used is approximately 58.8 ks i (4X 10'MPa). Heat the preform to approximately 550'F (28 Dewaxing is carried out at 7°C) and then vacuum dewaxing is carried out to ensure complete removal. Purif Place the foam in a fluid mold made of approximately 3=1 ceramic and glass, and and rapidly heat to about 2250'F (1220C). Purge the furnace with argon However, it takes about 2 hours to reach 22506F (1220°C).

The heated sample contained in the fluid mold is then placed in a press with slow release. and then exposed to a pressure of approximately 120 ksi (8.2 x 10" MPa) for approximately 2 seconds. Recovery. The refractory body has a density of about 10% of the theoretical value.

Approximately 3% by weight cobalt (5% by volume) and approximately 97% by weight tungsten carbide (95% by volume) The method of Example 1 is repeated including the composition of %). Pre-foam contained in fluid mold After heating the chamber to approximately 2370OF (1240℃), the isostatic pressure expose to force. The recovered refractory material has a density of approximately 99% (relative to the theoretical value). Ru.

Examples 3-9 Substantially similar to Example 1, about 6% by weight cobalt and about 94% by weight carbide Prepare several mixtures of ungsten. These mixtures are made into a silastic fluid Cold compression in a mold using approximately 0.5% by volume wax under a pressure of approximately 41.2 MPa. do. The cold press is heated to about 290°C to remove wax. The length of the rod is The length is approximately 0.563 inches (1,4α) and the diameter is approximately 0.75 inches (1,9 cm). It has a weight of about 36.67 jp.

The cold compressed body is then placed in a glass/ceramic pressure transmission medium and placed in an argon atmosphere. Heat to desired temperature in air and keep at that temperature for about 5 minutes. Cold compressed body in pressure transmission medium isostatic for the indicated dwell time with a manual pressure release of 2 seconds. Pressure is applied. The results are shown in Table 1.

Table 1 341.2 83.5 11002 225 B513.05441.2 83 ．． 5 1100'4 186--13.075 41.2 83.5 115 02 2238613.06641.2 B15 1220 11790 I 4.99741.2 83.5 12202 1459315.02841.2 B3.5 13002 2258715.00941.2 B3.5 130 02 2139515.03 Fine tungsten carbide powder (426B, 9) Weighed finely ground cobalt (272g) and 100011 parts of acetone. I did it with This composition is approximately 94% tungsten carbide (90 volume x) by weight. Approximately 6% cobalt by weight (10 volumes!X). Approximately 1,201 g of this slurry bs (55kl?) with 3/16” (1,2cm) diameter WC grinding media. Place in a Nion Process Model 1-8 attrition mill. powder at 250 rpm 2 hours of wear and tear. Acetone is removed by evaporation, resulting in approximately 225% fine parallax by volume. Copress the Finwax with 1000 #l/hebutane and abrade for 15 minutes.

The resulting slurry is evaporated to dryness.

Next, sieve the powder through a 45-mesh sieve to remove any large clumps. except. The Trexlow is then loaded into 9 Isopress bags, with a concentration of about 30% of theory to about Vibrate until a density of 40°C is reached. After suctioning the bag and sealing it, the theory of approx. approximately 30,000 psi (20,6X Isostatically pressurize at 10'MPa).

The rod-shaped body thus obtained was processed into Rosmas (U.S. Pat. No. 4,428,906). Place it in a similar fluid mold and fill it with borosilicate glass waste. this Heat the assembly to about 2250C (1232C) (about 165 hours) and purge with nitrogen. Keep in oven for 5 minutes. The assembly is placed into a support mold approximately 120ksi (8,2X10” Apply a pressure of (MPa) and hold for 2 seconds. Release the pressure gradually (approximately 12 ksi/ sec or 80MPa/5ec) o The refractory material to be recovered is 14.8i/c It has a density of more than m''.

Example 11 Weigh the niobium carbide powder (4086g) and add it immediately to prevent oxidation or burning. Place in seton (1000a(). Add cobalt and weigh about 90,96' The composition is niobium carbide (91% by volume) and about No% cobalt (9% by volume). child of slurry was abraded and processed under conditions substantially similar to Example 10 to achieve a density of approximately 7. Obtain a refractory object of 609/an3.

Example 12 Fine tungsten carbide powder (4268, p) is weighed to form fine nickel powder ( 272,! 9) Combine with. This powder was slurried with 100OLt of acetone. It is formed into a leech shape and is abraded and treated in the green state in substantially the same manner as in Example 1o.

The composition of the powder is approximately 959 tungsten carbide by weight (91% by volume) and 5% by weight. of nickel (9% by volume). Next, put the unfired material into a ceramic container and Surround with Ilex and heat at about 21506F for about 2 hours.

Then about 120! Apply a pressure of <5i (8,2X10'MPa) for 2 seconds and gradually (approximately 12 ksi/see or 80 MPa/5ec). thus obtained The part has a density of approximately 99.7% of theory.

A sample of nickel powder (250g) and nickel powder (251) was tested for abrasion. Approximately 90% by weight of nickel 7-elite and 1 by weight are physically mixed without A composition consisting of 0% nickel is obtained. This powder was then passed through a single-shaft dual-acting machine. It is compressed at approximately 58.8 ks i (8.2 mPa).

Do not use wax. The pellet thus obtained has a density of about 68% of theory. .

This part was placed in a glass mold similar to Example io and heated at approximately 2000°C for 2 hours. do. Pressure (approximately 120 ksi) was then applied for a residence time of 2 seconds, and then Release gradually. The ceramic thus obtained has a density of approximately 97.8% of the theoretical value. .

about 42689 tungsten carbide, about 2279 cobalt and about 45F nickel Add the mixture to 100Q #7 acetone. The composition of the abraded powder is approximately 94% tungsten carbide (90 vol. x) 15% cobalt (8.5 vol.%)/ Approximately 1% nickel (1.5% by volume). Powder was prepared substantially in the same manner as in Example 10. The ends are abraded, processed and compressed. The ceramic you get is about 14.66.9/ It has a density of a=.

Example 15A Mix tungsten carbide powder (4268 g) with cobalt powder (z7z, 9) and After being worn out, it was cold compressed in substantially the same manner as in Example 10, and the weight was approximately 94X. of tungsten carbide (90% by volume) and about 6% cobalt (10% by volume) give. This rod-shaped body was further heat-pressed in substantially the same manner as in Example 10. Approximately 0.5 inches (1,25 cm) in diameter and approximately 25 inches (6,35 cm) long The final rod-shaped body is The end of this rod-shaped body was mechanically processed to perform a standard pendulum impact test. It is made to fit the grip of the test machine and is broken by impact. Table 2 shows the results. Shown below.

Comparative Example 15B A rod having substantially the same composition and cold compressed body shape as that produced in Example 15A. The body is also produced by liquid phase sintering as carried out by experts in this field. It is processed and subjected to an impact test. The results are shown in Table 2.

A rod having substantially the same composition and cold compressed body shape as that produced in Example 15A. The body was prepared and densified to about 90X of theoretical density by short b-sintering cycles, and then Press to full density. These rod-shaped bodies were also processed at the ends in the same manner as above, and @ Put it to the impact test. The results are shown in Table 2.

15A (rod-shaped body according to the present invention) 2.33GN/m” 168015B (liquid phase firing 1.16GN/m"] 59015C (pressure densification after sintering) rod-shaped body) 1.22 ON/m” 1670 manufactured substantially in accordance with the present invention The rod-shaped body (Example 15A) is a rod-shaped body molded by liquid phase sintering or sintered and then It shows greater impact energy and hardness than rod-shaped bodies manufactured by pressurized densification. vinegar. Impact energy is required to break a strongly supported specimen due to impact from a palm tree. equal to the energy required to

Scanning electron microscope image of the sample of Example 15A (backscattered image at 4000x magnification) is shown in FIG. 4, a similar image of Example 15B is shown in FIG. 2 (C), and a similar image of Example 15B is shown in FIG. )K, it is clear that the boundary material (mainly cobalt) is present in the hot-pressed sample. Well distributed. The tungsten carbide phase that appears bright in this photo is relatively circular. The many small lines that look strange and are present on the photo are cobalt tungsten carbide. This suggests that it is contained only in extremely thin boundaries between particles. With this is significantly different, and the liquid phase sintered material of Figure 2 (Example 15B) has This is typical of the microstructure found in liquid-phase sintered materials with coarse to coarse grain size. Carbonized Nungsten particles are characterized by a characteristic between light tungsten carbide and dark-toned cobalt. It forms a block with sharp edges and sharp edges. especially , if we focus on the almost black areas of cobalt material in Figure 2, they are It seems to correspond to crystallographic tungsten carbide particles with many facets. It can be seen that many of the shapes are triangular or trapezoidal. As described in Example 15c For samples of It was demonstrated that such a sample actually has the properties of a sintered sample. In order to do this, it seems necessary to use an analytical transmission electron microscope.

We also draw a grid of straight lines on the diagram and find that these lines are rich in cobalt. By counting the frequency of intersections with materials that can be identified as boundary phases, The frequency of such intersections is as follows for the hot press material of FIG. 4 (Example 15A): At least twice as high as that for the liquid phase sintered material of Figure 2 (Example 15B) can be found. In the case of Example 15C, it is intermediate and confirms that This requires a precise analytical transmission electron microscope.

Example 16A Substantially similar to the procedure of Example 10, about 94% tungsten carbide and about 6% Prepare a cobalt abrasive blend of Cold compress into a disk shape. This disk was further prepared substantially as in Example 10. Heat press to form the final disk.

Comparative Example 16B prepared in Example 16A by liquid phase sintering as performed by experts in this field. Another disc of substantially the same composition and cold compact shape as that produced is produced.

from both sets of disks and also sintered and pressed substantially according to Example 15A. From each of the densified rods, a rod-shaped test piece for transverse fracture testing is machined. Ru. The machining and testing of these specimens was performed in accordance with ASTM Standards 1976 Yearbook, Vol. This field according to ASTM B406-73, Part 9, pp. 193-194. This is done by methods known to experts. The results are shown in Table 3.

Example】7 A cold compressed rod was prepared in the same manner as in Example 14, and the pressing temperature was increased to 2. Other than approximately 2150'F (1176°C) instead of 250'F'' (1232°C) is the same (hot-pressed in the same manner as in Example 14).

A rod-shaped test piece was prepared in the same manner as in Example 14 and subjected to an impact test. The O density to obtain the impact energy measurement of b/1n2 (4,23 GN/m2) is 13 The Gateskars hardness value, measured at 6 g/Crn (approximately 90% of theory), is due to this composition. at 1,100, which is considerably lower than the value of about 1,700 typical for a fully dense sample of It is recognized that there is.

Example 18A Substantially the method of Example 10 was repeated using tungsten carbide (4472,9) and Kobal) ( 98.5% by weight tungsten carbide (98.5% by weight). 7.4% by volume) and 1.5% by weight of cobalt (λ6 volume trace). P After heating the renovation to approximately 2250'F (1232C), isostatic apply pressure. The refractory objects to be recovered have the properties shown in Table 3.

Comparative Example 18B It has a composition and cold compact shape substantially similar to that prepared in Example 18A. Similar rods are prepared by liquid-phase sintering, as carried out by experts in this field. Evaluate accordingly. The results are shown in Table 3 for comparison.

Example 19A Substantially using tungsten carbide (4403g) and Kobal) (237,!9) 97% by weight tungsten carbide (98% by weight) by repeating the method of Example 1O. , 8 volumes iX) and 3% by weight of Kobal) (1,2% by volume). . After heating the preform to approximately 22501' (1232°C), the isostatic expose to pressure. The refractory objects to be recovered have the properties shown in Table 3.

Comparative Example 19B It has substantially the same composition and cold compaction shape as that prepared in Example 19A. rods prepared by liquid-phase sintering, such as that carried out by experts in this field. and evaluate in the same way. This fruit! A typical J image of SJ is shown in Figure 3. (Amelie (Refer to Metals Handbook, 9th edition, Volume 3, page 454, 198o, published by Kametal Association) 0 Practically implemented using tungsten carbide (381C9) and cobalt (726g) By repeating the method of Example 10, s4mt% tungsten carbide (74,6 % by volume) and 16% by weight of Kobal) (25.4% by volume). Purif After heating the foam to approximately 2250'F (1232°C), the isostatic pressure expose to force. The refractory objects to be recovered have the properties shown in Table 3.

Comparative Example 20B In Example 20A, using liquid phase sintering, as performed by experts in the field. preparing a rod having a composition and cold compaction shape substantially similar to that of the prepared rod; Evaluate in the same way. The results are shown in Table 3 for comparison. Typical of this example A microscopic image is shown in FIG. (Published by the American Institute of Metals, Metals Handbook, 9th edition, See Vol. 3, p. 454, 198o. ) Example 21A Example using titanium boride (4449!) and nickel (91,!9) By repeating the method in step 10, titanium diboride with a content of 98N (99 volume x) and 2% by weight of nickel (1% by volume).

After heating the preform to approximately 2550'F (1400C), the isostatic subject to intense pressure. The recovered refractory material has the properties shown in Table 3.

having a composition and cold compact shape substantially similar to that prepared in Example 21A. A rod-shaped body is prepared by liquid phase sintering as carried out by experts in the field 1 and Evaluate in the same way. The results are shown in Table 3 for comparison.

Titanium carbide (3178g), molybdenum carbide (817g) and nickel (545g) ，! 9) by substantially repeating the procedure of Example 10 using of titanium carbide (81,1 volumes), 18% by weight of molybdenum carbide and 122 volumes of nickel (7.7% by volume). Heat the preform to 2250°F ( 1232°C) and then exposed to isostatic pressure. Recovered fireproofing The object has the properties shown in Table 3.

Comparative Example 22B 1. In Example 22A, by liquid phase sintering as performed by experts in this field. A rod-like body having a composition and cold-pressed body shape substantially similar to that prepared by Evaluate in the same way. The results are shown in Table 3 for comparison.

A typical microscope image of this example is shown in FIG. (R, to Biswand 7+, D , J. Lofritz and J. Garland, eds., Science Ophard Materials. 'Microstructures of cemented carbide M, E, Exna ), p. 245, 1983).

Example 23A Substantially the same as Example 10 using alumina (3x7sl) and chromium (1362g) By repeating the process, approximately 70% alumina by weight (approximately 80.6% by volume) and approximately A composition of 30% by weight chromium (19.4% by volume) is prepared. Preform approx. After heating to 2876'F (1580°C) K, subject to isostatic pressure. . The recovered refractory material has the properties shown in Table 3.

Comparative Example 23B prepared in Example 23A by liquid phase sintering as performed by experts in the field. A rod-shaped body having substantially the same composition and cold-compressed body shape as the manufactured one is prepared and the same process is carried out. Evaluate. The results are shown in Table 3 for comparison.

Example 24A Boron carbide (4813g), molybdenum (204g), nickel (14g) and By essentially repeating the method of Example 10 using iron (9 g), about 95 g. % by weight of boron carbide (approximately 98.7 volume iX), approximately 4.5% by weight of molybdenum (approximately 1. 15% by weight), approximately 0.3% by weight of nickel (approximately 0.0% by weight) and approximately 0.2% by weight. A crude product of % iron (approximately 0.06% by volume) is prepared. Approximately 2372 preforms After heating to a low temperature (1300°C), it is exposed to isostatic pressure. collected The refractory object has the properties shown in Table 3.

prepared in Example 24A by liquid phase sintering as performed by experts in the field. A rod-shaped body having substantially the same composition and shape as the cold-compressed body was prepared and the same process was carried out. Evaluate. The results are shown in Table 3 for comparison.

Zirconium nitride (4267μ), nickel (227,9) and molybdenum (4 94 by substantially repeating the method of Example 1O using % zirconium nitride (approximately 95.1% by volume), approximately 5% nickel (approximately 4.1% by volume) tX) and about 1% by weight molybdenum (about 0.7% by volume).

After heating the preform to approximately 24986F (1370C), expose to pressure. The recovered refractory objects have the properties shown in Table 3.

Comparative Example 25B prepared in Example 25A by liquid phase sintering as performed by experts in the field. A rod-shaped body having substantially the same composition and shape as the cold-compressed body was prepared and similarly evaluated. do. The results are shown in Table 3 for comparison.

Practically killed using lanthanum chromate (4403g) and chromium (136g) By repeating step 0, about 97% by weight of lanthanum chromate (about 97% by weight) was obtained. 5% by volume) and about 3% by weight chromium (about 25% by volume). . Isostatically after heating the preform to approximately 2876°F (1580°C) expose to pressure. (b) The collected refractory material has the properties shown in Table 3.

Comparative Example 26B Liquid phase sintering as performed by experts in this field ((thus, in Example 26A) A rod having a composition and cold compaction shape substantially similar to that prepared by Evaluate in the same way. The results are shown in Table 3 for comparison.

Substantially Example 1 using silicon nitride (4313F) and aluminum (2279) By repeating method 0, approximately 95% by weight silicon nitride (approximately 94.2 volume = X) and about 5% by weight aluminum (about 5.8% by volume). Purifo After heating the chamber to approximately 1220°F (660°C), apply isostatic pressure. Expose. The recovered refractory material has the properties shown in Table 3.

Comparative Example 27B By liquid phase sintering as performed by experts in this field, the ↓ Rods having substantially the same composition and shape as the cold compressed body were prepared and similarly tested for liver value. Ru. The results are shown in Table 6 for comparison.

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Claims (1)

[Claims] 1. Oxides, carbides, nitrides, silicides, borides, sulfides and mixtures thereof a refractory material selected from the group consisting of The plastically deformable binder material present in sufficient weight to partially seal has a toughness approximately 10% greater than that exhibited by other composite ceramics of similar composition and geometry. A high-density refractory composite ceramic consisting of a densified refractory material. 2. The ceramic is substantially pre-sintered prior to final densification with other composite ceramics. The composite cell according to claim 1, which has a toughness 10% greater than the toughness exhibited by the material. Ramitsuk. 3. A composite ceramic according to claim 2, wherein the ceramic has a toughness of 15% greater. Mitsuku. 4. A composite ceramic according to claim 2, wherein the ceramic has a toughness of 25% greater. Mitsuku. 5. 3. The composite ceramic of claim 2, wherein said composite ceramic has a binder material distribution that is 10% greater than other composite ceramics of similar composition. 6. 3. A composite ceramic according to claim 2, wherein said composite ceramic has a binder material distribution that is 50% greater than a composite ceramic of similar composition. 7. 3. A composite ceramic according to claim 2, wherein said composite ceramic has a binder material distribution that is 100% greater than other composite ceramics of similar composition. 8. 3. The composite ceramic of claim 2, wherein said composite ceramic has an average grain size of less than about 10 microns. 9. 3. The composite ceramic of claim 2, wherein said composite ceramic has an average grain size of less than about 5 microns. 10. 3. The composite ceramic of claim 2, wherein said composite ceramic has an average grain size of less than about 2 microns. 11. 3. The composite ceramic of claim 2, wherein said composite ceramic has an average grain size of less than about 1 micron. 12. The composite ceramic has an average grain size of less than about 10 microns. Composite ceramic according to claim 5. 13. 3. The composite ceramic of claim 2, wherein said composite ceramic has an average circularity value of less than about 17. 14. 3. The composite ceramic of claim 2, wherein said composite ceramic has an average circularity value of less than about 15.5. 15. 3. The composite ceramic of claim 2, wherein said composite ceramic has an average circularity value of less than about 14. 16. 3. The composite ceramic of claim 2, wherein said composite ceramic has an average circularity value of less than about 13.2. 17. The composite ceramic is 10% larger than other composite ceramics of similar composition. Composite ceramic according to claim 1.3, having a narrow binder material distribution. 18. The composite ceramic has an average grain size of less than about 10 microns. Composite ceramic according to item 17. 19. 3. The composite ceramic of claim 2, wherein the composite ceramic has a toughness that is 10% greater and a hardness that is at least approximately equal to that of other composite ceramics of similar composition and shape. Combined Ceramics. 20. Binder materials include cobalt, nickel, iron, tungsten, molybdenum, and tan. metal, titanium, chromium, niopium, boron, zirconium, vanadium, silicon, Radium, hafnium, aluminum, copper, their alloys and mixtures thereof 3. The composite ceramic according to claim 2, which is selected from the group consisting of: 21. 21. The composite ceramic of claim 20, comprising about 50 to about 99.5% by volume refractory material and about 0.5 to about 50% by volume binder material. 22. 21. The composite ceramic of claim 20, comprising about 70 to about 995% by volume refractory material and about 0.5 to about 30% by volume binder material. 23. 21. The composite ceramic of claim 20 comprising about 80 to about 94% by volume refractory material and about 6 to about 20% by volume binder material. 24. (a) Alumina, zirconia, magnesia, mullite, zircon, thoria, beryllia, urania, spinel, tungsten carbide, tantalum carbide, titanium carbide Nioprene carbide, zirconium carbide, boron carbide, hafnium carbide, silicon carbide, niobium boron carbide, aluminum nitride, titanium nitride, zirconium nitride, tantalum nitride, hafnium nitride, niopium nitride, boron nitride, silicon nitride, titanium boron Tan, chromium boride, zirconium boride, tantalum boride, molybdenum boride, tungsten boride, cerium sulfide, molybdenum sulfide, cadmium sulfide, zinc sulfide, titanium sulfide, magnesium sulfide, zirconium sulfide, and mixtures thereof. (b) a refractory material selected from the group consisting of; and (b) cobalt, nickel, titanium, and ROM, niopium, boron, palladium, hafnium, silicon, tantalum, molybdenum, zircoetham, vanadium, aluminum, copper, alloys thereof, and mixtures thereof. 3. A composite ceramic according to claim 2, comprising a binder material selected from the group consisting of composites. 25(a) Tungsten carbide, niobium carbide, titanium carbide, silicon carbide, niobium carbide Refractory material selected from the group consisting of boron boron, tantalum carbide, boron carbide, alumina, silicon nitride, boron nitride, titanium nitride, titanium boride and mixtures thereof. and (b) cobalt, nickel, titanium, chromium, niopium, palladium, a binder material selected from the group consisting of fnium, tantalum and mixtures thereof; A composite ceramic according to claim 2, comprising: 26. (a) Tungsten carbide, niopium carbide, titanium carbide and mixtures thereof (b) a refractory material selected from the group consisting of; and (b) cobalt, niopium, titanium and Claim 2 comprising a binder material selected from the group consisting of mixtures thereof. Composite ceramics. 27. Composite ceramic according to claim 2, comprising tungsten carbide and cobalt. Tsuku. 28. 28. The composite ceramic of claim 27 comprising about 50 to about 99.5% tungsten carbide by volume and about 0.5 to about 50% cobalt by volume. 29. 28. The composite ceramic of claim 27, comprising about 80 to about 99.5% tungsten carbide by volume and about 0.5 to about 20% cobalt by volume. 30. A steel material consisting of approximately 94% tungsten carbide by volume and approximately 6% cobalt by volume. The method according to claim 27. 31. a refractory material selected from the group consisting of oxides, carbides, nitrides, borides, sulfides and mixtures thereof; and a plasticizer present in an amount sufficient to at least partially fill the interstices between the particles of the refractory material. The binder material, which is capable of deformation, is bonded under a pressure between approximately 10,000 psi (6.89 x 101 MPa) and the breaking point of the refractory. At temperatures lower than the liquidus temperature of the composite material, the ceramic composite loses its theoretical density. 10% greater toughness than that exhibited by other composite ceramics of similar composition and geometry over a period of time sufficient to reach 85% of the hardness and sufficient time to cause sintering. 1. A method for producing a high-density refractory composite ceramic, the method comprising: contacting the composite ceramic under conditions such as to provide a high-density refractory body having a density of 85% or more. 32. 32. The method of claim 31, wherein the pressure is applied isostatically. 33. 33. The method of claim 32, wherein the refractory body has a toughness that is 10% greater than that exhibited by other refractory bodies that have been substantially presintered prior to final densification. 34. 34. The method of claim 33, wherein the refractory object has 15% greater toughness. 35. 34. The method of claim 33, wherein the refractory object has 25% greater toughness. 36. Composite ceramics have a 10% higher bond than other composite ceramics of similar composition. 34. The method according to claim 33, having a mixture material distribution. 37. 34. The method of claim 33, wherein the composite ceramic has an average grain size of less than about 10 microns. 38. Composite ceramics have a 10% higher bond than other composite ceramics of similar composition. 34. The method according to claim 33, having a mixture material distribution. 39. 34. The method of claim 33, wherein the composite ceramic has an average circularity value of less than about 17. 40. 34. The method of claim 33, wherein the composite ceramic has 10% greater toughness and at least approximately equal hardness compared to other composite ceramics of similar composition and shape. 41. Binder materials include cobalt, nickel, iron, tungsten, molybdenum, and tan. metal, titanium, chromium, niobium, boron, zirconium, panadium, silicon, metal Fnium, palladium, aluminum, copper, their alloys and mixtures thereof 34. The method of claim 33, wherein the method is selected from the group consisting of: 42. (a) about 50 to about 99.5% by volume of a refractory material selected from the group consisting of oxides, carbides, nitrides, silicides, borides, sulfides, and mixtures thereof; 42. The method of claim 41, wherein the contacting is with 0.5 to about 50% binder material. 43. 34. The method of claim 33, wherein the pressure is between about 50,000 psi (3.4 x 102 MPa) and about the breaking point of the refractory body. 44. 34. The method of claim 33, wherein the pressure is between about 70,000 psi (4.8 x 102 MPa) and about the breaking point of the refractory body. 45. The pressure is approximately 100,000psi (6.89X102MPa) and is almost refractory. 34. The method of claim 33, wherein the pressure is between the breaking points of the body. 46. 34. The method of claim 33, wherein the temperature is about 400 to about 2900<0>C. 47. 34. The method of claim 33, wherein the contact time is less than about 1 hour. 48. 34. The method of claim 33, wherein the contact time is less than about 1 minute. 49. 34. The method of claim 33, wherein the contact time is less than about 10 seconds. 50. (a) Alumina, zirconia, magnesia, mullite, zircon, thoria, beryllia, urania, spinel, tungsten carbide, tantalum carbide, titanium carbide Nioprene carbide, zirconium carbide, boron carbide, hafnium carbide, silicon carbide, boron carbide, aluminum nitride, titanium nitride, zirconium nitride, titanium nitride hafnium nitride, niopium nitride, boron nitride, silicon nitride, titanium boride, chromium boride, zirconium boride, tantalum boride, molybdenum boride, tungsten boride, cerium sulfide, molybdenum sulfide, cadmium sulfide, zinc sulfide, (composed of titanium sulfide, magnesium sulfide, zirconium sulfide and mixtures thereof) (b) cobalt, nickel, titanium, chromium, niopium, boron, palladium, hafnium, silicon, tantalum, molybdenum, silica; Conium, vanadium, aluminum, copper, their alloys and mixtures thereof 34. The method of claim 33, wherein the contacting agent is a binder material selected from the group consisting of: 51. (a) Tungsten carbide, niopium carbide, titanium carbide, silicon carbide, boron carbide (b) cobalt, nickel, titanium, chromium, niop; palladium, hafniu contact with a binder material selected from the group consisting of aluminum, tantalum or mixtures thereof. 34. The method according to claim 33. 52. (a) Tungsten carbide, niopium carbide, titanium carbide and mixtures thereof (b) a refractory material selected from the group consisting of; (b) cobalt, niopium, titanium and 34. The method of claim 33, wherein the contacting agent is a binder material selected from the group consisting of a mixture of: 53. 34. The method of claim 33, wherein tungsten carbide is contacted with cobalt. 54. 54. The method of claim 53, wherein the temperature is about 800<0>C to about 1500<0>C. 55. 54. The method of claim 53, wherein the contact time is less than 1 hour. 56. 54. The method of claim 53, wherein the contact time is less than 1 minute. 57. 54. The method of claim 53, wherein the contact time is less than 10 seconds. 58. at least partially filling gaps between particles of the refractory material and a material selected from the group consisting of oxides, carbides, nitrides, borides, sulfides and mixtures thereof; A plastically deformable binder material present in a sufficient amount to cause the liquid phase of the binder material to melt under a pressure between about 10,000 psi (6.89 x 101 MPa) and the breaking point of the refractory material. less than a sufficient time for the composite ceramic to reach a density of 85% of its theoretical density at a temperature below the line temperature and a sufficient time for sintering to occur. contacting the material under conditions such as to provide a dense refractory body having a density of 85% or more with a toughness 10% greater than that exhibited by other composite ceramics for a period of time between A high-density refractory ceramic composite manufactured by 59. The ceramic composite according to claim 58, in which pressure is applied to the isostatic Combined. 60. 60. The ceramic of claim 59, wherein the composite has a toughness greater than that exhibited by other ceramic composites that have been substantially pre-sintered prior to final densification. Tsuku complex. 61. 61. The ceramic of claim 60, wherein said ceramic has 15% greater toughness. Mitsuku complex. 62. 61. The ceramic of claim 60, wherein the ceramic has 25% greater toughness. Mitsuku complex. 63. Binder materials include cobalt, nickel, iron, tungsten, molybdenum, and tan. metal, titanium, chromium, niopium, boron, zirconium, vanadium, silicon, Radium, hafnium, aluminum, copper, their alloys and mixtures thereof 61. A composite ceramic according to claim 60, selected from the group consisting of: 64. (a) about 50 to about 99.5% oxides, carbides, nitrides, silicides, borides, sulfides, and mixtures thereof in terms of solubility; (b) about 0.5 to about 50% in solubility; 64. The composite ceramic of claim 63, wherein the composite ceramic is contacted with a binder material of . 65. 61. The composite ceramic of claim 60, wherein the pressure is between about 50,000 psi (3.4 x 102 MPa) and the breaking point of the refractory body. 66. 61. The composite ceramic of claim 60, wherein the pressure is between about 70,000 psi (4.8 x 102 MPa) and the breaking point of the refractory body. 67. 61. The composite ceramic of claim 60, wherein the pressure is between about 100,000 psi (6.89 x 101 MPa) and the breaking point of the refractory body. 68. 61. The composite ceramic of claim 60, wherein the temperature is from about 400<0>C to about 2900<0>C. 69. 61. The composite ceramic of claim 60, wherein the contact time is less than about 1 hour. 70. 61. The composite ceramic of claim 60, wherein the contact time is less than about 1 minute. 71. 61. The composite ceramic of claim 60, wherein the contact time is less than about 10 seconds. 72. (a) Alumina, zirconia, magnesia, mullite, zircon, thoria, beryllia, urania, spinel, tungsten carbide, tantalum carbide, titanium carbide Nioprene carbide, zirconium carbide, boron carbide, hafnium carbide, silicon carbide, boron carbide, aluminum nitride, titanium nitride, zirconium nitride, titanium nitride hafnium nitride, niopium nitride, boron nitride, silicon nitride, titanium boride, chromium boride, zirconium boride, tantalum boride, molybdenum boride, tungsten boride, cerium sulfide, molybdenum sulfide, cadmium sulfide, zinc sulfide, (b) a refractory material selected from the group consisting of titanium sulfide, magnenium sulfide, zirconium sulfide and mixtures thereof; (b) cobalt, nickel, titanium, chromium, nickel; Op, boron, palladium, hafnium, silicon, tantalum, molybdenum, zirco 61. The composite cell of claim 60 in contact with a binder material selected from the group consisting of aluminum, vanadium, aluminum, copper, alloys thereof and mixtures thereof. Ramitsuk. 73. (a) Tungsten carbide, niopium carbide, titanium carbide, silicon carbide, boron carbide (b) a refractory material selected from the group consisting of tantalum carbide, boron carbide, alumina, silicon nitride, boron nitride, titanium nitride, titanium boride and mixtures thereof; palladium, hafniu contact with a binder material selected from the group consisting of aluminum, tantalum and mixtures thereof. The composite ceramic according to claim 60. 74. (a) Tungsten carbide, niopium carbide, titanium carbide and mixtures thereof (b) a refractory material selected from the group consisting of; (b) cobalt, niopium, titanium and 61. The composite ceramic of claim 60, wherein the composite ceramic is contacted with a binder material selected from the group consisting of mixtures of. 75. 61. The composite ceramic according to claim 60, wherein tungsten carbide is brought into contact with cobalt. 76. 76. The composite ceramic of claim 75, wherein the temperature is about 800<0>C to about 1500<0>C. 77. 77. The compound of claim 76, wherein the temperature is about 1000°C to about 1350°C. Combined Ceramics. 78. 77. The composite ceramic of claim 76, wherein the contact time is less than 1 hour. 79. 77. The composite ceramic of claim 76, wherein the contact time is less than 1 minute. 80. 77. The composite ceramic of claim 76, wherein the contact time is less than 10 seconds. 81. (a) oxides, carbides, nitrides, silicides, borides and mixtures thereof; (b) a binder material capable of plastic deformation; and (c) a binder material on a grid of refractory material. the binder material and component (c) are present in an amount sufficient to at least partially fill the interstices between the particles of the refractory material. Object ceramic complex. 82. Binder materials include cobalt, iron, nickel, tungsten, molybdenum, and tan. metal, titanium, chromium, niopium, boron, zirconium, vanadium, silicon, Fnium, palladium, aluminum, copper, their alloys and mixtures thereof and (c) corresponds to the formula Xa-bYbZc, where X is a metal derived from a refractory material; Y is a binder material capable of plastic deformation; and Z is carbon, oxygen, nitrogen, silicon, boron or sulfur; α is an integer from about 1 to about 4; b is a real number from about 0.001 to about 0.2; and c is an integer from about 1 to about 4. Adjustment 82. The composite ceramic according to claim 81, which is a number. 83. 82. The refractory material of claim 81, comprising: about 50 to about 99% by weight refractory material; about 1 to about 50% by weight binder; metal; and about 0.001 to about 2% by weight component (c). Composite ceramic. 84. Oxides, carbides, nitrides, silicides, borides, sulfides, and mixtures thereof a refractory material selected from the group consisting of 10% greater binder material distribution than that exhibited by other composite ceramics of similar composition and shape, with a binder material distribution of plastically deformable binder material present in sufficient quantity to partially fill the binder material and less than about 17 A dense refractory composite ceramic consisting of a densified refractory body having an average circularity value of .